Frequent Questions

Does hydrogen sulfide present in the ground count towards the TPQ and RQ?

A petroleum company is drilling for oil contained in the ground below their facility. Would the hydrogen sulfide present in the ground be counted toward the threshold planning quantity (TPQ) for this extremely hazardous substance (EHS) under Section 302? Also, if there is a reportable release of this EHS above the reportable quantity (RQ) during this operation, would this release need to be reported under Section 304?

On July 26, 1990, (55 FR 30632), EPA revised the definition of facility to include manmade structures as well as all natural structures in which chemicals are purposefully placed or removed through human means such that it functions as a containment structure for human use. So, if the facility is generating hydrogen sulfide during its drilling operations, then the quantity they generate must be included in the TPQ determination for hydrogen sulfide. The facility is producing or causing the hydrogen sulfide to be present and is therefore subject to Section 302 reporting. A release of hydrogen sulfide above its RQ that affects persons off-site must be reported under Section 304 of EPCRA since the release would occur from the facility.